Visualizer, measurement system, and measurement method

Abstract

A state visualizer according to one aspect of the present disclosure includes an optical member including a fixed part that has a fixed relative positional relationship with an object to be measured and a movable part that is movably supported by the fixed part and keeps a constant angle with respect to a gravity direction, the optical member retroreflecting a light or an electromagnetic wave in a case where the fixed part and the movable part are in a predetermined positional relationship. The optical member changes an intensity of the light or the electromagnetic wave reflected in a retroreflection direction in accordance with a change of a relative positional relationship between the fixed part and the movable part.

What is claimed is: 
     
       1. A visualizer, comprising:
 an optical member including a fixed part that has a fixed relative positional relationship with an object to be measured and a movable part that is movably supported by the fixed part and keeps a constant angle with respect to a gravity direction, the optical member retroreflecting a light or an electromagnetic wave from outside of the visualizer to outside of the visualizer in a case where the fixed part and the movable part are in a predetermined positional relationship, wherein: 
 the optical member changes an intensity of the light or the electromagnetic wave reflected in a retroreflection direction in accordance with a change of a relative positional relationship between the fixed part and the movable part, 
 the optical member includes a liquid that is held by the fixed part, and 
 the movable part is supported by the fixed part only through the liquid. 
 
     
     
       2. The visualizer according to  claim 1 , wherein:
 the optical member includes a first mirror having a first mirror surface, a second mirror having a second mirror surface, and a third mirror having a third mirror surface, the first mirror surface, the second mirror surface, and the third mirror surface intersecting and facing one another, 
 the first mirror is included in the fixed part, 
 the second mirror is included in the movable part and is supported by the fixed part through the liquid so that the second mirror surface keeps a constant angle with respect to the gravity direction, and 
 the optical member changes the intensity of the light or the electromagnetic wave reflected in the retroreflection direction in accordance with a change of an angle formed between the first mirror surface and the second mirror surface. 
 
     
     
       3. The visualizer according to  claim 1 , wherein a specific gravity of the liquid is larger than a specific gravity of the movable part. 
     
     
       4. A measurement system, comprising:
 one or more visualizers according to  claim 1 ; 
 a lighting device that emits a light or an electromagnetic wave toward the one or more visualizers mounted on an object to be measured; 
 an imaging device that takes an image including the object to be measured and the one or more visualizers; and 
 a measurement device that measures a change of a relative positional relationship between the fixed part and the movable part in the one or more visualizers on a basis of a change of an intensity of reflected light or a reflected electromagnetic wave from the one or more visualizers in the image. 
 
     
     
       5. The measurement system according to  claim 4 , wherein
 the imaging device includes a plurality of cameras or a compound-eye camera; and 
 the measurement device detects a light distribution of the reflected light or the reflected electromagnetic wave on a basis of a plurality of images taken by the plurality of cameras or the compound-eye camera. 
 
     
     
       6. The measurement system according to  claim 4 , wherein
 the lighting device includes a plurality of light sources; and 
 the plurality of light sources emit light beams or electromagnetic waves that are different from one another in terms of at least one of a wavelength, a polarization state, and an irradiation timing. 
 
     
     
       7. A measurement method comprising:
 emitting light or an electromagnetic wave to one or more visualizers according to  claim 1  attached to an object to be measured; 
 taking an image including a reflected light or a reflected electromagnetic wave from the one or more visualizers; and 
 measuring a state of the object to be measured on a basis of the image. 
 
     
     
       8. The visualizer according to  claim 1 , wherein the movable part floats on the liquid. 
     
     
       9. The visualizer according to  claim 1 , further comprising a housing holding the liquid,
 wherein the fixed part is fixed to and disposed in the housing. 
 
     
     
       10. The visualizer according to  claim 1 , wherein the fixed part includes a reference mirror and a bias mirror that is disposed so as to be tilted forward with respect to the reference mirror. 
     
     
       11. The visualizer according to  claim 10 , wherein each of the reference mirror and the bias mirror each has a linear prism shape. 
     
     
       12. The visualizer according to  claim 1 , wherein the movable part has a triangular prism shape.